Abstract

Aim: Quantum dot, composed of II-VI family elements or III-V family elements, is one kind of important nanoparticles which bears unique optical properties confined by tridimensional restriction of quantum. As the quantum dot-tagged nerve growth factor (NGF) nanoparticles belong to nanometer grade, it is easy to pass through the biomembrane of cells. This experiment aims to explore the effect of treating brain injured rats by transplanting amniotic-derived mesenchymal stem cells (AD-MSCs) carried with such nanoparticles. Methods: This experiment was undertaken in Zhengzhou University from January to October in 2007. 1 Materials: Forty SPF healthy Wistar rats were evenly divided into four groups according to their body weight: NGF nanoparticle cell group, normal cell group, brain injury model group and control group of nutrient medium. Rats in the experiment were disposed according to the animal ethics. Human AD-MSCs were extracted from the placenta amniosis of healthy parturient by professor Yang Bo working in the First Affiliated Hospital of Zhengzhou University. All the parturients signed informed consents. Moreover, the experiment was approved by the Medical Ethical Committee of the hospital. Quantum dot-tagged NGF nanoparticles were constructed with the assistance of the State Key Laboratory of Applied Organic Chemistry of Lanzhou University. 2 Empirical methods: AD-MSCs were added to nutritive medium DMEM/F12 which contained 10% calf serum and 20 μ g/L basic fibroblast growth factor. Cells were then cultivated in an incubator of saturated humidity at 37 °C, with 0.05 volume fraction of CO2 nutritive medium. When 80%-90% cells were mixed, trypsinization and was underwent and cells were subcultured. The cells in the third generation was added with quantum dot-tagged NGF nanoparticles at different final concentrations of 20, 40, 60 μ g/L respectively, then modified 72 hours. Blank controls and empty quantum dot controls were set up. Brain injured models were constructed to all the rats in four groups according to Feeney's free fall method. The injured part of rats in NGF nanoparticle cell group was injected with 10 μ L AD-MSCs suspension at the final concentration of 40 mg/L, which was modified by quantum dot-tagged NGF nanoparticles (about 4.0 × 108 cells). Normal cell group was injected with 10 μ L AD-MSCs suspension only labeled by quantum dot. Control group of nutrient medium was injected with 10 μ L cell nutrient medium DMEM/F12. Yet nothing would be transplanted into the brain injury model group. 3 Experiment evaluation: After modifying NGF nanoparticle labeled by quantum dot, MTT method was used to detect cytoactivity. Fluorescence microscope was used to observe the distribution of quantum dots in cells. Immunocytochemistry was adopted to identify cell differentiation. After cell transplantation, the movement and sensory function of rats in all the groups were scored. Immunohistochemical dying and fluorescence microscopy were employed to observe the survival and migration of AD-MSCs labeled by quantum dots. Results: 1 Cell growth rate: After cultivating for 72 hours, the growth rate of cells in NGF nanoparticles labeled by quantum dots at the concentrations of 20, 40, 60 μ g/L increased apparently compared with that in blank control group and empty quantum dot group. There was no obvious growth inhibition when the concentration was 40 μ g/L, and the increase of growth rate began to slow when the concentration was 60 μ g/ L. 2 The distribution of quantum dots in vitro: Fluorescence microscope was used to observe AD-MSCs, NGF nanoparticle labeled by quantum dots were injected 6 hours later. The intake increased as time went by and reached the highest level 32 hours later. 3 The immunocytochemistry evaluation in vitro: AD-MSCs modified by quantum dot-labeled NGF nanoparticle expressed neuronal enolase and neurofilament protein, then differentiated into neurons, but the cells didn't express glial fibrillary acidic protein. 4 Detection of neuroethology: All the indexes in neuroethology of rats among those groups were similar 24 hours after transplantation (P > 0.05); After transplanting 10 and 20 days, there was no significant difference between brain injury model group and control group of nutrient medium, whereas the scores of the movement and sensory function decreased significantly in NGF nanoparticle cell group and normal cell group (P < 0.05), particularly, the decrease of NGF nanoparticle cell group was more obvious than that of normal cell group (P < 0.05). 5 The immunohistochemistry and fluorescence detection results: AD-MSCs modified by NGF nanoparticle labeled by quantum dots survived in the brain injured area and migrated to the surrounding area. Conclusion: Quantum dot is a kind of good tracer agents for cells. Transplanting the AD-MSCs modified by NGF nanoparticle labeled by quantum dots is a good way to improve the nerve function of brain injured rats.

abstract = "Aim: Quantum dot, composed of II-VI family elements or III-V family elements, is one kind of important nanoparticles which bears unique optical properties confined by tridimensional restriction of quantum. As the quantum dot-tagged nerve growth factor (NGF) nanoparticles belong to nanometer grade, it is easy to pass through the biomembrane of cells. This experiment aims to explore the effect of treating brain injured rats by transplanting amniotic-derived mesenchymal stem cells (AD-MSCs) carried with such nanoparticles. Methods: This experiment was undertaken in Zhengzhou University from January to October in 2007. 1 Materials: Forty SPF healthy Wistar rats were evenly divided into four groups according to their body weight: NGF nanoparticle cell group, normal cell group, brain injury model group and control group of nutrient medium. Rats in the experiment were disposed according to the animal ethics. Human AD-MSCs were extracted from the placenta amniosis of healthy parturient by professor Yang Bo working in the First Affiliated Hospital of Zhengzhou University. All the parturients signed informed consents. Moreover, the experiment was approved by the Medical Ethical Committee of the hospital. Quantum dot-tagged NGF nanoparticles were constructed with the assistance of the State Key Laboratory of Applied Organic Chemistry of Lanzhou University. 2 Empirical methods: AD-MSCs were added to nutritive medium DMEM/F12 which contained 10{\%} calf serum and 20 μ g/L basic fibroblast growth factor. Cells were then cultivated in an incubator of saturated humidity at 37 °C, with 0.05 volume fraction of CO2 nutritive medium. When 80{\%}-90{\%} cells were mixed, trypsinization and was underwent and cells were subcultured. The cells in the third generation was added with quantum dot-tagged NGF nanoparticles at different final concentrations of 20, 40, 60 μ g/L respectively, then modified 72 hours. Blank controls and empty quantum dot controls were set up. Brain injured models were constructed to all the rats in four groups according to Feeney's free fall method. The injured part of rats in NGF nanoparticle cell group was injected with 10 μ L AD-MSCs suspension at the final concentration of 40 mg/L, which was modified by quantum dot-tagged NGF nanoparticles (about 4.0 × 108 cells). Normal cell group was injected with 10 μ L AD-MSCs suspension only labeled by quantum dot. Control group of nutrient medium was injected with 10 μ L cell nutrient medium DMEM/F12. Yet nothing would be transplanted into the brain injury model group. 3 Experiment evaluation: After modifying NGF nanoparticle labeled by quantum dot, MTT method was used to detect cytoactivity. Fluorescence microscope was used to observe the distribution of quantum dots in cells. Immunocytochemistry was adopted to identify cell differentiation. After cell transplantation, the movement and sensory function of rats in all the groups were scored. Immunohistochemical dying and fluorescence microscopy were employed to observe the survival and migration of AD-MSCs labeled by quantum dots. Results: 1 Cell growth rate: After cultivating for 72 hours, the growth rate of cells in NGF nanoparticles labeled by quantum dots at the concentrations of 20, 40, 60 μ g/L increased apparently compared with that in blank control group and empty quantum dot group. There was no obvious growth inhibition when the concentration was 40 μ g/L, and the increase of growth rate began to slow when the concentration was 60 μ g/ L. 2 The distribution of quantum dots in vitro: Fluorescence microscope was used to observe AD-MSCs, NGF nanoparticle labeled by quantum dots were injected 6 hours later. The intake increased as time went by and reached the highest level 32 hours later. 3 The immunocytochemistry evaluation in vitro: AD-MSCs modified by quantum dot-labeled NGF nanoparticle expressed neuronal enolase and neurofilament protein, then differentiated into neurons, but the cells didn't express glial fibrillary acidic protein. 4 Detection of neuroethology: All the indexes in neuroethology of rats among those groups were similar 24 hours after transplantation (P > 0.05); After transplanting 10 and 20 days, there was no significant difference between brain injury model group and control group of nutrient medium, whereas the scores of the movement and sensory function decreased significantly in NGF nanoparticle cell group and normal cell group (P < 0.05), particularly, the decrease of NGF nanoparticle cell group was more obvious than that of normal cell group (P < 0.05). 5 The immunohistochemistry and fluorescence detection results: AD-MSCs modified by NGF nanoparticle labeled by quantum dots survived in the brain injured area and migrated to the surrounding area. Conclusion: Quantum dot is a kind of good tracer agents for cells. Transplanting the AD-MSCs modified by NGF nanoparticle labeled by quantum dots is a good way to improve the nerve function of brain injured rats.",

N2 - Aim: Quantum dot, composed of II-VI family elements or III-V family elements, is one kind of important nanoparticles which bears unique optical properties confined by tridimensional restriction of quantum. As the quantum dot-tagged nerve growth factor (NGF) nanoparticles belong to nanometer grade, it is easy to pass through the biomembrane of cells. This experiment aims to explore the effect of treating brain injured rats by transplanting amniotic-derived mesenchymal stem cells (AD-MSCs) carried with such nanoparticles. Methods: This experiment was undertaken in Zhengzhou University from January to October in 2007. 1 Materials: Forty SPF healthy Wistar rats were evenly divided into four groups according to their body weight: NGF nanoparticle cell group, normal cell group, brain injury model group and control group of nutrient medium. Rats in the experiment were disposed according to the animal ethics. Human AD-MSCs were extracted from the placenta amniosis of healthy parturient by professor Yang Bo working in the First Affiliated Hospital of Zhengzhou University. All the parturients signed informed consents. Moreover, the experiment was approved by the Medical Ethical Committee of the hospital. Quantum dot-tagged NGF nanoparticles were constructed with the assistance of the State Key Laboratory of Applied Organic Chemistry of Lanzhou University. 2 Empirical methods: AD-MSCs were added to nutritive medium DMEM/F12 which contained 10% calf serum and 20 μ g/L basic fibroblast growth factor. Cells were then cultivated in an incubator of saturated humidity at 37 °C, with 0.05 volume fraction of CO2 nutritive medium. When 80%-90% cells were mixed, trypsinization and was underwent and cells were subcultured. The cells in the third generation was added with quantum dot-tagged NGF nanoparticles at different final concentrations of 20, 40, 60 μ g/L respectively, then modified 72 hours. Blank controls and empty quantum dot controls were set up. Brain injured models were constructed to all the rats in four groups according to Feeney's free fall method. The injured part of rats in NGF nanoparticle cell group was injected with 10 μ L AD-MSCs suspension at the final concentration of 40 mg/L, which was modified by quantum dot-tagged NGF nanoparticles (about 4.0 × 108 cells). Normal cell group was injected with 10 μ L AD-MSCs suspension only labeled by quantum dot. Control group of nutrient medium was injected with 10 μ L cell nutrient medium DMEM/F12. Yet nothing would be transplanted into the brain injury model group. 3 Experiment evaluation: After modifying NGF nanoparticle labeled by quantum dot, MTT method was used to detect cytoactivity. Fluorescence microscope was used to observe the distribution of quantum dots in cells. Immunocytochemistry was adopted to identify cell differentiation. After cell transplantation, the movement and sensory function of rats in all the groups were scored. Immunohistochemical dying and fluorescence microscopy were employed to observe the survival and migration of AD-MSCs labeled by quantum dots. Results: 1 Cell growth rate: After cultivating for 72 hours, the growth rate of cells in NGF nanoparticles labeled by quantum dots at the concentrations of 20, 40, 60 μ g/L increased apparently compared with that in blank control group and empty quantum dot group. There was no obvious growth inhibition when the concentration was 40 μ g/L, and the increase of growth rate began to slow when the concentration was 60 μ g/ L. 2 The distribution of quantum dots in vitro: Fluorescence microscope was used to observe AD-MSCs, NGF nanoparticle labeled by quantum dots were injected 6 hours later. The intake increased as time went by and reached the highest level 32 hours later. 3 The immunocytochemistry evaluation in vitro: AD-MSCs modified by quantum dot-labeled NGF nanoparticle expressed neuronal enolase and neurofilament protein, then differentiated into neurons, but the cells didn't express glial fibrillary acidic protein. 4 Detection of neuroethology: All the indexes in neuroethology of rats among those groups were similar 24 hours after transplantation (P > 0.05); After transplanting 10 and 20 days, there was no significant difference between brain injury model group and control group of nutrient medium, whereas the scores of the movement and sensory function decreased significantly in NGF nanoparticle cell group and normal cell group (P < 0.05), particularly, the decrease of NGF nanoparticle cell group was more obvious than that of normal cell group (P < 0.05). 5 The immunohistochemistry and fluorescence detection results: AD-MSCs modified by NGF nanoparticle labeled by quantum dots survived in the brain injured area and migrated to the surrounding area. Conclusion: Quantum dot is a kind of good tracer agents for cells. Transplanting the AD-MSCs modified by NGF nanoparticle labeled by quantum dots is a good way to improve the nerve function of brain injured rats.

AB - Aim: Quantum dot, composed of II-VI family elements or III-V family elements, is one kind of important nanoparticles which bears unique optical properties confined by tridimensional restriction of quantum. As the quantum dot-tagged nerve growth factor (NGF) nanoparticles belong to nanometer grade, it is easy to pass through the biomembrane of cells. This experiment aims to explore the effect of treating brain injured rats by transplanting amniotic-derived mesenchymal stem cells (AD-MSCs) carried with such nanoparticles. Methods: This experiment was undertaken in Zhengzhou University from January to October in 2007. 1 Materials: Forty SPF healthy Wistar rats were evenly divided into four groups according to their body weight: NGF nanoparticle cell group, normal cell group, brain injury model group and control group of nutrient medium. Rats in the experiment were disposed according to the animal ethics. Human AD-MSCs were extracted from the placenta amniosis of healthy parturient by professor Yang Bo working in the First Affiliated Hospital of Zhengzhou University. All the parturients signed informed consents. Moreover, the experiment was approved by the Medical Ethical Committee of the hospital. Quantum dot-tagged NGF nanoparticles were constructed with the assistance of the State Key Laboratory of Applied Organic Chemistry of Lanzhou University. 2 Empirical methods: AD-MSCs were added to nutritive medium DMEM/F12 which contained 10% calf serum and 20 μ g/L basic fibroblast growth factor. Cells were then cultivated in an incubator of saturated humidity at 37 °C, with 0.05 volume fraction of CO2 nutritive medium. When 80%-90% cells were mixed, trypsinization and was underwent and cells were subcultured. The cells in the third generation was added with quantum dot-tagged NGF nanoparticles at different final concentrations of 20, 40, 60 μ g/L respectively, then modified 72 hours. Blank controls and empty quantum dot controls were set up. Brain injured models were constructed to all the rats in four groups according to Feeney's free fall method. The injured part of rats in NGF nanoparticle cell group was injected with 10 μ L AD-MSCs suspension at the final concentration of 40 mg/L, which was modified by quantum dot-tagged NGF nanoparticles (about 4.0 × 108 cells). Normal cell group was injected with 10 μ L AD-MSCs suspension only labeled by quantum dot. Control group of nutrient medium was injected with 10 μ L cell nutrient medium DMEM/F12. Yet nothing would be transplanted into the brain injury model group. 3 Experiment evaluation: After modifying NGF nanoparticle labeled by quantum dot, MTT method was used to detect cytoactivity. Fluorescence microscope was used to observe the distribution of quantum dots in cells. Immunocytochemistry was adopted to identify cell differentiation. After cell transplantation, the movement and sensory function of rats in all the groups were scored. Immunohistochemical dying and fluorescence microscopy were employed to observe the survival and migration of AD-MSCs labeled by quantum dots. Results: 1 Cell growth rate: After cultivating for 72 hours, the growth rate of cells in NGF nanoparticles labeled by quantum dots at the concentrations of 20, 40, 60 μ g/L increased apparently compared with that in blank control group and empty quantum dot group. There was no obvious growth inhibition when the concentration was 40 μ g/L, and the increase of growth rate began to slow when the concentration was 60 μ g/ L. 2 The distribution of quantum dots in vitro: Fluorescence microscope was used to observe AD-MSCs, NGF nanoparticle labeled by quantum dots were injected 6 hours later. The intake increased as time went by and reached the highest level 32 hours later. 3 The immunocytochemistry evaluation in vitro: AD-MSCs modified by quantum dot-labeled NGF nanoparticle expressed neuronal enolase and neurofilament protein, then differentiated into neurons, but the cells didn't express glial fibrillary acidic protein. 4 Detection of neuroethology: All the indexes in neuroethology of rats among those groups were similar 24 hours after transplantation (P > 0.05); After transplanting 10 and 20 days, there was no significant difference between brain injury model group and control group of nutrient medium, whereas the scores of the movement and sensory function decreased significantly in NGF nanoparticle cell group and normal cell group (P < 0.05), particularly, the decrease of NGF nanoparticle cell group was more obvious than that of normal cell group (P < 0.05). 5 The immunohistochemistry and fluorescence detection results: AD-MSCs modified by NGF nanoparticle labeled by quantum dots survived in the brain injured area and migrated to the surrounding area. Conclusion: Quantum dot is a kind of good tracer agents for cells. Transplanting the AD-MSCs modified by NGF nanoparticle labeled by quantum dots is a good way to improve the nerve function of brain injured rats.